Thanks for the help :-)
Cheers,
Cornelius
On Sun, Dec 7, 2008 at 10:33 AM, Steve Smith <[log in to unmask]> wrote:
> Hi,
>
> Each EV is in effect task vs. rest, so yes a [-1 -1 -1] (equivalent to your
> contrast) does the rest > mean-task contrast that you want.
>
> Cheers.
>
>
>
> On 6 Dec 2008, at 10:44, Cornelius Werner wrote:
>
>> Hi there,
>>
>> I searched the archives without apparent success, so I need to put up
>> the question myself.
>>
>> I have a simple 3-condition block design paradigm, interrupted by
>> resting period. I modeled all three active conditions, leaving the rest
>> period unmodeled. Now, I would like to see the "inverse" contrast, i.e.
>> "rest" > (task1 + task2 + task3). As far as I understood, there is no
>> way of getting an unmodeled condition into a contrast. I tried to create
>> a contrast like
>>
>> - -0.33 -0.33 -0.33
>>
>> in the hope that the resting codition would receive an implicit contrast
>> weight of 1, but results are very unconvincing.
>>
>> What could a solution look like?
>>
>> Thanks for any help!
>> Cornelius
>>
>>
>>
>> --
>> Dr. med. Cornelius J. Werner
>> GnuPG Public Key ID: 0x9D64BC2C
>>
>> Institute of Neuroscience and Biophysics - INB3
>> Research Centre Juelich
>> 52425 Juelich
>> Germany
>>
>> Department of Psychiatry and Psychotherapy
>> RWTH Aachen University
>> Pauwelsstr. 30
>> 52074 Aachen
>> Germany
>>
>> ::: Please encrypt confidential data :::
>>
>
>
> ---------------------------------------------------------------------------
> Stephen M. Smith, Professor of Biomedical Engineering
> Associate Director, Oxford University FMRIB Centre
>
> FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
> +44 (0) 1865 222726 (fax 222717)
> [log in to unmask] http://www.fmrib.ox.ac.uk/~steve
> ---------------------------------------------------------------------------
>
--
Dr. med. Cornelius J. Werner
GnuPG Public Key ID: 0x9D64BC2C
Institute of Neuroscience and Biophysics - INB3
Research Centre Juelich
52425 Juelich
Germany
Department of Psychiatry and Psychotherapy
RWTH Aachen University
Pauwelsstr. 30
52074 Aachen
Germany
::: Please encrypt confidential data :::
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